Searching Drupal Files with Ack
Ack is a recursive grep-replacement Perl script that you can download from: http://betterthangrep.com It is somewhat similar to "egrep", but is much smarter and has ten times nicer output format. It also automatically ignores annoying .svn files and you can teach it different file types.
If you are a Drupal developer you need to put the following line in your /etc/profile:
After which you can enjoy yourself some:
ack --php "check_plain"